Neoplasias, including bladder, renal, and prostate cancers, are a significant cause of human morbidity and mortality. Bladder cancer is the fourth most common cancer in men and the eighth in women both in terms of incidence and mortality; renal cancer kills approximately 12,000 Americans every year, and 30,000 new cases of renal cancer are reported each year in the United States; and prostate cancer is clinically diagnosed in one of every 11 American men. One third of men diagnosed will prostate cancer will develop a life threatening disease In their earliest stages, bladder, renal, and prostate neoplasias are clinically silent. When and if clinical symptoms do develop, patient diagnosis typically involves invasive procedures that lack sensitivity and accuracy. Highly reliable, noninvasive screening methods would permit patient screening, diagnosis, and prognostic evaluation. In addition, such methods would be useful for monitoring patients during or after cancer therapy.